Answer:
The age of the rock = 2800.6 million years = 2.8 billion years.
A simple method of analysis similar to Carbon dating is used to obtain the required age of the rock. Radioactive substances decay according to first order reaction kinetics. So, plugging all the required parameters into the general equation for amount of substance left in a first order decay gives us the age of the rock.
Explanation:
Half life of Uranium-235 = 700 million years (from literature)
The decay of radioactive substances follow first order reaction kinetics.
The general equation is given as
A(t) = A₀ e⁻ᵏᵗ
A(t) = Amount of radioactive substance left after a particular time = 6.25%
A₀ = initial amount of radioactive substance = 100%
t = time that has passed since the beginning = age of the rock = ?
k = decay constant
The decay constant is related to the half life (T) through the relation,
k = (In 2)/T
k = (0.693/700) = 0.00099 /million years
A(t) = A₀ e⁻ᵏᵗ
6.25 = 100 e⁻ᵏᵗ
0.0625 = e⁻ᵏᵗ
In e⁻ᵏᵗ = In 0.0625 = -2.7726
-kt = - 2.7726
t = (2.7726/0.00099) = 2800.6 million years
t = 2.8 billion years.
Hope this Helps!!!
Answer:
The three smallest countries in the world are:
- Vatican City (it is a country)
- Monaco
- Nauru
Answer:
Mesosphere lies in between 50 to 80 km above the earth surface and due to low density gases escape easily and hence it is colder.
Explanation:
Mesosphere has the capacity to not absorb the infrared radiation that's why the gases reflected from the earth surface escape the layer of mesopause and goes inside the thermosphere.
In the thermosphere, even the minute atoms of gases ca be absorbed by the layer which increases the air temperature and the air rises up hence making thermosphere as the hottest layer in the atmosphere.
#SPJ2
Answer:
the answer is basically the first sentences in each paragraph combined (see below)
Explanation:
Your summary is about the fights between India and Pakistan. Including background knowledge and the after effects.
Hope this helps :)
